mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-11-10 15:14:43 +00:00
fe3dde3e7b
Allow the kaslr-seed value in the chosen node to be set from a hardware
rng source.
Tested on a Rockchip PX30 (Odroid Go Advance), you must have loaded
the devicetree first and prepared it for editing. On my device the
workflow goes as follows:
setenv dtb_loadaddr "0x01f00000"
load mmc 0:1 ${dtb_loadaddr} rk3326-odroid-go2.dtb
fdt addr ${dtb_loadaddr}
fdt resize
kaslrseed
and the output can be seen here:
fdt print /chosen
chosen {
kaslr-seed = <0x6f61df74 0x6f7b996c>;
stdout-path = "serial2:115200n8";
};
Signed-off-by: Chris Morgan <macromorgan@hotmail.com>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
81 lines
1.8 KiB
C
81 lines
1.8 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* The 'kaslrseed' command takes bytes from the hardware random number
|
|
* generator and uses them to set the kaslr-seed value in the chosen node.
|
|
*
|
|
* Copyright (c) 2021, Chris Morgan <macromorgan@hotmail.com>
|
|
*/
|
|
|
|
#include <common.h>
|
|
#include <command.h>
|
|
#include <dm.h>
|
|
#include <hexdump.h>
|
|
#include <malloc.h>
|
|
#include <rng.h>
|
|
#include <fdt_support.h>
|
|
|
|
static int do_kaslr_seed(struct cmd_tbl *cmdtp, int flag, int argc, char *const argv[])
|
|
{
|
|
size_t n = 0x8;
|
|
struct udevice *dev;
|
|
u64 *buf;
|
|
int nodeoffset;
|
|
int ret = CMD_RET_SUCCESS;
|
|
|
|
if (uclass_get_device(UCLASS_RNG, 0, &dev) || !dev) {
|
|
printf("No RNG device\n");
|
|
return CMD_RET_FAILURE;
|
|
}
|
|
|
|
buf = malloc(n);
|
|
if (!buf) {
|
|
printf("Out of memory\n");
|
|
return CMD_RET_FAILURE;
|
|
}
|
|
|
|
if (dm_rng_read(dev, buf, n)) {
|
|
printf("Reading RNG failed\n");
|
|
return CMD_RET_FAILURE;
|
|
}
|
|
|
|
if (!working_fdt) {
|
|
printf("No FDT memory address configured. Please configure\n"
|
|
"the FDT address via \"fdt addr <address>\" command.\n"
|
|
"Aborting!\n");
|
|
return CMD_RET_FAILURE;
|
|
}
|
|
|
|
ret = fdt_check_header(working_fdt);
|
|
if (ret < 0) {
|
|
printf("fdt_chosen: %s\n", fdt_strerror(ret));
|
|
return CMD_RET_FAILURE;
|
|
}
|
|
|
|
nodeoffset = fdt_find_or_add_subnode(working_fdt, 0, "chosen");
|
|
if (nodeoffset < 0) {
|
|
printf("Reading chosen node failed\n");
|
|
return CMD_RET_FAILURE;
|
|
}
|
|
|
|
ret = fdt_setprop(working_fdt, nodeoffset, "kaslr-seed", buf, sizeof(buf));
|
|
if (ret < 0) {
|
|
printf("Unable to set kaslr-seed on chosen node: %s\n", fdt_strerror(ret));
|
|
return CMD_RET_FAILURE;
|
|
}
|
|
|
|
free(buf);
|
|
|
|
return ret;
|
|
}
|
|
|
|
#ifdef CONFIG_SYS_LONGHELP
|
|
static char kaslrseed_help_text[] =
|
|
"[n]\n"
|
|
" - append random bytes to chosen kaslr-seed node\n";
|
|
#endif
|
|
|
|
U_BOOT_CMD(
|
|
kaslrseed, 1, 0, do_kaslr_seed,
|
|
"feed bytes from the hardware random number generator to the kaslr-seed",
|
|
kaslrseed_help_text
|
|
);
|